These are key combinations to activate System Recovery/Factory Restore so you can restore a laptop or desktop to factory settings with the onboard system recovery image.

System Recovery is not system restore. System restore is a windows only system

these key presses and procedures vary from brand to brand.

• Acer - Alt + F10
• Dell - Ctrl + F11 , Ctrl + F10
• HP - F10
• HP/Compaq - On startup, press f11 to launch Recovery Manager
  Pressing the f11 key during the startup on a computer with an HP factory image will start the system recovery process even if the prompt is not displayed
• Fujitsu -